iwlwifi:mvm: Add AP/GO channel switch support

Publish WIPHY_FLAG_HAS_CHANNEL_SWITCH if the fw supports
newly introduced IWL_UCODE_TLV_API_CSA_FLOW.
When CSA starts, save the switching vif inside mvm and during the CSA period
configure fw with a new beacon after each beacon transmission in order to
update the csa counters.
Also, handle correctly the CSA unbind-bind flow which is triggered by mac80211
when the actual channel switch happens.

Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Reviewed-by: Luciano Coelho <luciano.coelho@intel.com>
Reviewed-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>

5 files changed, 60 insertions, 2 deletions

diff --git a/drivers/net/wireless/iwlwifi/iwl-fw.h b/drivers/net/wireless/iwlwifi/iwl-fw.h
index f5927d0cf9b6..6fea27c0dd8e 100644
--- a/drivers/net/wireless/iwlwifi/iwl-fw.h
+++ b/drivers/net/wireless/iwlwifi/iwl-fw.h
@@ -116,9 +116,11 @@ enum iwl_ucode_tlv_flag {
 /**
  * enum iwl_ucode_tlv_api - ucode api
  * @IWL_UCODE_TLV_API_WOWLAN_CONFIG_TID: wowlan config includes tid field.
+ * @IWL_UCODE_TLV_API_CSA_FLOW: ucode can do unbind-bind flow for CSA.
  */
 enum iwl_ucode_tlv_api {
         IWL_UCODE_TLV_API_WOWLAN_CONFIG_TID     = BIT(0),
+        IWL_UCODE_TLV_API_CSA_FLOW              = BIT(4),
 };
 
 /**
diff --git a/drivers/net/wireless/iwlwifi/mvm/mac-ctxt.c b/drivers/net/wireless/iwlwifi/mvm/mac-ctxt.c
index 7110ec2605d6..56cf58e95698 100644
--- a/drivers/net/wireless/iwlwifi/mvm/mac-ctxt.c
+++ b/drivers/net/wireless/iwlwifi/mvm/mac-ctxt.c
@@ -1237,11 +1237,23 @@ int iwl_mvm_rx_beacon_notif(struct iwl_mvm *mvm,
         u32 rate __maybe_unused =
                 le32_to_cpu(beacon->beacon_notify_hdr.initial_rate);
 
+        lockdep_assert_held(&mvm->mutex);
+
         IWL_DEBUG_RX(mvm, "beacon status %#x retries:%d tsf:0x%16llX rate:%d\n",
                      status & TX_STATUS_MSK,
                      beacon->beacon_notify_hdr.failure_frame,
                      le64_to_cpu(beacon->tsf),
                      rate);
+
+        if (unlikely(mvm->csa_vif && mvm->csa_vif->csa_active)) {
+                if (!ieee80211_csa_is_complete(mvm->csa_vif)) {
+                        iwl_mvm_mac_ctxt_beacon_changed(mvm, mvm->csa_vif);
+                } else {
+                        ieee80211_csa_finish(mvm->csa_vif);
+                        mvm->csa_vif = NULL;
+                }
+        }
+
         return 0;
 }
 
diff --git a/drivers/net/wireless/iwlwifi/mvm/mac80211.c b/drivers/net/wireless/iwlwifi/mvm/mac80211.c
index db55d670dce0..34626249c685 100644
--- a/drivers/net/wireless/iwlwifi/mvm/mac80211.c
+++ b/drivers/net/wireless/iwlwifi/mvm/mac80211.c
@@ -320,6 +320,9 @@ int iwl_mvm_mac_setup_register(struct iwl_mvm *mvm)
         if (mvm->fw->ucode_capa.flags & IWL_UCODE_TLV_FLAGS_GO_UAPSD)
                 hw->wiphy->flags |= WIPHY_FLAG_AP_UAPSD;
 
+        if (mvm->fw->ucode_capa.api[0] & IWL_UCODE_TLV_API_CSA_FLOW)
+                hw->wiphy->flags |= WIPHY_FLAG_HAS_CHANNEL_SWITCH;
+
         hw->wiphy->iface_combinations = iwl_mvm_iface_combinations;
         hw->wiphy->n_iface_combinations =
                 ARRAY_SIZE(iwl_mvm_iface_combinations);
@@ -2198,6 +2201,11 @@ static int iwl_mvm_assign_vif_chanctx(struct ieee80211_hw *hw,
 
         switch (vif->type) {
         case NL80211_IFTYPE_AP:
+                /* Unless it's a CSA flow we have nothing to do here */
+                if (vif->csa_active) {
+                        mvmvif->ap_ibss_active = true;
+                        break;
+                }
         case NL80211_IFTYPE_ADHOC:
                 /*
                  * The AP binding flow is handled as part of the start_ap flow
@@ -2234,6 +2242,12 @@ static int iwl_mvm_assign_vif_chanctx(struct ieee80211_hw *hw,
                         goto out_remove_binding;
         }
 
+        /* Handle binding during CSA */
+        if (vif->type == NL80211_IFTYPE_AP) {
+                iwl_mvm_update_quotas(mvm, vif);
+                iwl_mvm_mac_ctxt_changed(mvm, vif);
+        }
+
         goto out_unlock;
 
  out_remove_binding:
@@ -2258,13 +2272,20 @@ static void iwl_mvm_unassign_vif_chanctx(struct ieee80211_hw *hw,
         iwl_mvm_remove_time_event(mvm, mvmvif, &mvmvif->time_event_data);
 
         switch (vif->type) {
-        case NL80211_IFTYPE_AP:
         case NL80211_IFTYPE_ADHOC:
                 goto out_unlock;
         case NL80211_IFTYPE_MONITOR:
                 mvmvif->monitor_active = false;
                 iwl_mvm_update_quotas(mvm, NULL);
                 break;
+        case NL80211_IFTYPE_AP:
+                /* This part is triggered only during CSA */
+                if (!vif->csa_active || !mvmvif->ap_ibss_active)
+                        goto out_unlock;
+
+                mvmvif->ap_ibss_active = false;
+                iwl_mvm_update_quotas(mvm, NULL);
+                /*TODO: bt_coex notification here? */
         default:
                 break;
         }
@@ -2360,6 +2381,25 @@ static int iwl_mvm_mac_testmode_cmd(struct ieee80211_hw *hw,
 }
 #endif
 
+static void iwl_mvm_channel_switch_beacon(struct ieee80211_hw *hw,
+                                          struct ieee80211_vif *vif,
+                                          struct cfg80211_chan_def *chandef)
+{
+        struct iwl_mvm *mvm = IWL_MAC80211_GET_MVM(hw);
+
+        mutex_lock(&mvm->mutex);
+        if (WARN(mvm->csa_vif && mvm->csa_vif->csa_active,
+                 "Another CSA is already in progress"))
+                goto out_unlock;
+
+        IWL_DEBUG_MAC80211(mvm, "CSA started to freq %d\n",
+                           chandef->center_freq1);
+        mvm->csa_vif = vif;
+
+out_unlock:
+        mutex_unlock(&mvm->mutex);
+}
+
 const struct ieee80211_ops iwl_mvm_hw_ops = {
         .tx = iwl_mvm_mac_tx,
         .ampdu_action = iwl_mvm_mac_ampdu_action,
@@ -2402,6 +2442,8 @@ const struct ieee80211_ops iwl_mvm_hw_ops = {
 
         .set_tim = iwl_mvm_set_tim,
 
+        .channel_switch_beacon = iwl_mvm_channel_switch_beacon,
+
         CFG80211_TESTMODE_CMD(iwl_mvm_mac_testmode_cmd)
 
 #ifdef CONFIG_PM_SLEEP
diff --git a/drivers/net/wireless/iwlwifi/mvm/mvm.h b/drivers/net/wireless/iwlwifi/mvm/mvm.h
index 1575ac7c5864..1e468c3e8dea 100644
--- a/drivers/net/wireless/iwlwifi/mvm/mvm.h
+++ b/drivers/net/wireless/iwlwifi/mvm/mvm.h
@@ -644,6 +644,8 @@ struct iwl_mvm {
 
         /* Indicate if device power save is allowed */
         bool ps_disabled;
+
+        struct ieee80211_vif *csa_vif;
 };
 
 /* Extract MVM priv from op_mode and _hw */
diff --git a/drivers/net/wireless/iwlwifi/mvm/ops.c b/drivers/net/wireless/iwlwifi/mvm/ops.c
index cd526e198ae2..f8530b329d17 100644
--- a/drivers/net/wireless/iwlwifi/mvm/ops.c
+++ b/drivers/net/wireless/iwlwifi/mvm/ops.c
@@ -220,7 +220,7 @@ static const struct iwl_rx_handlers iwl_mvm_rx_handlers[] = {
         RX_HANDLER(BA_NOTIF, iwl_mvm_rx_ba_notif, false),
 
         RX_HANDLER(BT_PROFILE_NOTIFICATION, iwl_mvm_rx_bt_coex_notif, true),
-        RX_HANDLER(BEACON_NOTIFICATION, iwl_mvm_rx_beacon_notif, false),
+        RX_HANDLER(BEACON_NOTIFICATION, iwl_mvm_rx_beacon_notif, true),
         RX_HANDLER(STATISTICS_NOTIFICATION, iwl_mvm_rx_statistics, true),
         RX_HANDLER(ANTENNA_COUPLING_NOTIFICATION,
                    iwl_mvm_rx_ant_coupling_notif, true),